Process for dyeing with anilin-black.



UNITED .s'rA'rns PATENT OFFICE.

HARTLEY FLETCHER, or THAON-LES-VOSGES, FRANCE, ASSIGNOR T0 ALPHONSE EMILE VERGE, or VINCENNES, FRANCE.

PROCES FOR DYEING WITH ANILIN-BLACK.

No Drawing.

Specification of Letters Patent.

Patented July 7,1914.

Application filed July 21, 1913. Serial No. 780,371.

for Dyeing with Anilin-Black, which is fully set forth in the following specification.

A process is known for obtaining amhn black on textile fibers or fabrics, produced by simple oxidation in the air, without any other oxidizing agent, the oxidizing taking place owing to the presence of an oxygen carrier on the one hand, and of a small quantity of a paradiamin or of a paramidophe- 1101, on the other hand. For that purpose, an impregnating bath composed of the following ingredients, has been employed: 25 grams of anilin, 1 gram of paraphenylene diamin, 7.5 grams of hydrochlonic acid, 7 .5 grams of 90% formic acid 24 grams of cuprous chlorid, 7 grams of sulfite, 70 grams of ammonium chlorid, and water'to complete one liter. The advantages claimed for that process, are as follows :a, considerable economy in the preparation of the foularding bath; 6, simplicity and cheapness of the apparatus required for the operation; 0, economy in the consumption of steam which is considerably reduced; d, practically negligible weakening of the fabrics treated. Considering only the last advantage, the importance of such a process appears very great, as it is possible to assert that, even at the same or a slightly higher price, an anilin black which does not weaken the fiber, must be greatly appreciated and quickly preferred to the usual blacks which it was hitherto practically impossible to obtain, Without considerably weakening the fabrics treated. But ,the above mentioned process gives in practice only very imperfect results, and in order to obtain good results, it is necessary to take into account the improvements forming the subject of this invention.

By applying the process in question, as'it has been described, and with an impregnating bath of the composition above referred to, thefollowing disadvantages will be noticed: 1. The black obtained is reddish, thin and easily becomes green. 2. The strength of the fabric itself is irre lar.

By the present invention, thefollowing conditions are fulfilled, which are of the greatest importance: a. A black is obtained dry sodium bi-' having" depth and strength at least equal to those of the oxidation black obtained up to now. 6. The black is obtainedwithout per ceptibly weakening the fiber treated. 0. A black 18 obtained which does not become green more than the best known oxidation blacks. The first of these conditions requires the use of a much greater quantity of anilin' than that given above, it being necessary to obtain a concentration approaching that used for the manufacture of oxidation blacks. The second condition is satisfied by considerably increasing the quantity of anilin relative to the quantity of acid used,

without however carrying the said increase to the point of precipitation. Finally, a black that does snot become green cannot be obtained with a small quantity of anilin, any more thanit could be obtained without a special finishing. It must be pointed out that the qualities of the black andits properties depend at least asmuch on the finish ing as on the preparation, and on the manner in which the oxidation is carried out.

The composition of the impregnating bath which gives excellent results, is as follows":

45 grams of anilin, 6 grams of paraphenylene diamin, 35 grams of hydrochloric acid, 10 grams of 90% formic acid, 6 grams of copper sulfate, 3 grams of sodium bisulfite and water to complete one liter.

As will be seen, the impregnating bath differs from the baths previously specified by a considerable increase in the quantity of anilin oil and-,of paraphenylene-diamin, by a considerable decrease in the quantity of copper salts and sodium bisulfite used and by the entire leaving out of ammonium chlorid.

The fabric is impregnated by passing it several times through the bath and then drying on drums, but incompletely, so as to leave approximately 25% of moisture which will facilitate the oxidation, or the fabric, is" preferably dried thoroughly, and then passed through a vaporizing chamber saturated with moisture, whereby a more regular degree of moisture can be obtained. The pieces can be then suspended for 4'8 hours in a hanging room or left in a heap during the same period, aerating them from time to "time so asto produce oxidation in the air. As regards {1E finishing treatment to which the fabrics or fibers must be submitted, itcan take place either during the chromating or after the said chromating. If the treatment takes place during chromating, it consists in adding a certain quantity of anilin (about 4 to the sodium bichromate bath. The

. fabrics or fibers impregnated with this bath,

are subsequently heated to a given temperature above 50, or the fabrics or fibers are impregnated in a cold bath, and the impregnated pieces are heated by passing them over drums without completely drying them. If the operation is carried out afterthe chromating, the fabric or the fibers are passed through a bath of anilin salt (about -j,-%), and the operation above -referred to' for the case where the finishing is done during chro-niat-ing is proceeded with. In that way, a black is obtained, the shade and the resistance to becoming green of which correspfind to those of the existing oxidation blac 4 I claim: I

The process of dyeing textile material with anilin black by oxidation in the air, which consists in impregnating the material in a bath composed of 5 grams of anilin, 6 grams of pa/raphenylene diamin, 35 grams of hydrochloric acid, 10 grams of 90% formic acid, 6 grams of copper sulfate, 3 grams of dry sodium bisulfite, and water to complete one liter; drying the impregnated material; and finally subjecting said material to a finishing treatment.

In testimony whereof I have signed this specification in the presence of two subscribing witnesses.

HARTLEY FLETCHER.

Witnesses:

EMILE LEDRET, LUCIEN MEMMINGER. 

